In a scanning electron microscope (SEM) or the like, which measures and inspects, for example, a semiconductor wafer, position checking of a field of view (FOV) or a scanning position to a desired measurement position is carried out, by using pattern matching technique. JP-A-2001-243906 (corresponding U.S. Pat. No. 6,627,888) explains an example of such a pattern matching method.
A pattern matching is carried out by measurement of coincidence between a pattern image, which is called a template and registered in advance, and an image obtained actually by SEM or the like. JP-A-2002-328015 (corresponding: US2003/0173516) explains an example of forming a template for pattern matching, based on a design data of a semiconductor element or the like. Formation of the template based on the design data has an advantage in that bothering to obtain an SEM image or the like can be eliminated.
JP-A-2003-90719 (corresponding U.S. Pat. No. 6,872,943) and JP-A-2004-251674 (corresponding: US2004/0222375) explain a technique to prevent failure in pattern matching caused by mistaking between a depression and a protrusion, by understanding a depression/protrusion state of a pattern, wherein the same shape monotonously continues, like line/space.
Because a template formed based on a design data is a drawing expressed by only lines which define a contour of a pattern, in the case of a pattern, wherein the same shape is monotonously repeated, like line/space, there is a problem that determination between a pattern portion and a non-pattern portion is difficult.
In particular, in the case of a line/space pattern, if the edge of a line pattern is located outside FOV, due to high magnification, there is a problem that it is difficult to determine which of a line part (a protrusion), or a space part (a depression), a region defined by two lines corresponds to. Techniques disclosed in Patent Documents 3 and 4 were directed to depression/protrusion determination in a SEM image, and not to depression/protrusion determination in a design data.